Cambrian: Opinion

Look for turf battles as big male elephant seals return to beach

A pair of male elephant seals fight in late November during a previous mating season.
A pair of male elephant seals fight in late November during a previous mating season. Special to The Cambrian

Late November is on the cusp between the young elephant seals’ resting period and the adult seals’ dramatic season of birthing and mating. While juveniles and subadult males are still on the beaches, the huge adult males begin to arrive.

The first one came in last week. He is an adult male, judging from the length and shape of his nose — called a proboscis — and the beginnings of the callus on his neck that we call a chest shield. These two characteristics suggest the age of a male, who becomes mature at about 8 years old.

Only the males grow the proboscis and it doesn’t start to show until they are about 5 years old. The chest shield begins later and grows and thickens with age.

This first guy to arrive was bigger than the subadult males on the beach, but he was a wannabe, not large enough to be a contender for the title of alpha male. He may have gotten here first, but he is likely to be deposed by a bigger, older fellow.

For the next few weeks, before the pregnant females start to show up, the adult males, arriving from their foraging migration to Alaska, will vie for territory on the beach. Each one will want to be an alpha, big, strong and tough (or mean) enough to keep other males away from a harem of up to about 40 females.

His first attempt at becoming dominant is his voice. Booming and echoing, it may be all it takes to send another male searching for a different spot on the beach — or not. The other male may have a bigger voice. If they decide that they are about the same size, they may fight, with sharp canine teeth drawing blood. It usually looks worse than it is, and one guy inevitably gives up.

In December, the females come in, each one searching for a safe place to deliver her pup. By then the hierarchy of the males is fairly well established and each apparent alpha will have females gathering around him. Why does he want them? Each mother will nurse her pup for a month and then mate again, with him. That’s what it’s all about. But things can change.

Sometimes a bigger, tougher guy will arrive later and scare or fight off an apparent alpha. The action can be dramatic and fun to watch.

The juveniles and subadult males — the equivalent of teenagers — will be gone by the time the pups are being born, headed to sea on their migrations after fasting for a month or so. None of the elephant seals eat while they are here. The adult males, who can weigh 5,000 pounds and be 16 feet long when they arrive, won’t eat for about three months, living off their stored fat during that time. That’s why they’re so big when they get here.

If we can rely on Mother Nature’s calendar, by late December some pups will be born and the beaches will be packed with mothers, pups and alpha males throughout January and February.